The disclosure relates to a method for producing a multilayer system with joining elements, these being produced in particular from plastic, to a corresponding multilayer system and to a corresponding use.
Multilayer systems are used in a wide variety of areas of technology. For instance, DE 695 15 84 T2 discloses a multilayer system which is formed by a repair paint with special effect pigments. DE 695 04 923 T2 furthermore discloses a magnetoresistance sensor with a self-polarized multilayer system.
Furthermore, optical elements in the form of multilayer systems are also known. For instance, DE 20 2009 015 334 U1 discloses an optically active multilayer system for solar absorption, comprising a reflection layer and an absorber layer, an antireflection layer being arranged between the reflection layer and the absorber layer. Also arranged between the absorber layer and the reflection layer is a further layer and an optically active layer of a metal compound with a stoichiometric composition.
DE 102 22 574 A1 discloses a method for producing a multilayer system and a multilayer system with a first layer, which comprises a first at least partially chemically polymerized monomer and a monomer which is at least partially polymerized by light curing, and with at least one second layer, which comprises a second at least partially chemically polymerized monomer, the first and second monomers forming polymers which extend across the interface between the first and second layers. Such a method has the disadvantage in particular that it is only to a very limited extent that different materials can be used for the individual layers.
Furthermore, the applicant is familiar from a reference with the practice of connecting various layers of a multilayer system to one another by means of adhesive bonding. It is in this case disadvantageous, however, that a strength or reliability of an adhesively bonded connection between the various layers is determined by the forces of adhesion between the adhesive and the respective layers of the multilayer system and the cohesion of the adhesive itself.
Finally, DE 197 53 846 A1 discloses a welding method for welding color plastic profiles. Welding has the advantage over adhesive bonding that there is no need for the adhesive, or adhesives, to be applied and cured. In the case of welding, however, the respective layers are melted, that is to say they expand on account of the development of heat. When a welded seam is created, they subsequently contract again. As a result, intrinsic mechanical stresses are included in the region of the welded seam, impairing the strength of the welded connection. Therefore, if, for example, the coefficients of thermal expansion of a first and a second layer that are to be joined together to form a (multi-)layer system are very different in magnitude, correspondingly higher mechanical stresses occur. In the case of multiple layers that are to be respectively connected by means of welding, these stresses increase and the risk of a rupture of a welded seam at some point in the multilayer system increases considerably.
If the multilayer system is also exposed to further mechanical and/or thermal loads in further processing steps, this risk is once again increased significantly.